switch project to webpack based build

[x1B]

After successfully switching laxar and the react- and angular-adapters to a webpack-based build, let's be consistent and continue with laxar-patterns.

Also, the i18n helper library currently uses the stateful module laxar.i18n (which is no-longer existing in LaxarJS v2). That dependency must be passed in by clients instead.

[x1B]

Implemented on master (v2.0).

BREAKING CHANGE

To support stateless LaxarJS modules, the handlerFor factory API of i18n and validation was changed:

• The validation.handlerFor expects two additional arguments: configuration (the configuration of the current laxarjs bootstrapping context) and log (the logger of the current laxarjs bootstrapping context),
• The i18n.handlerFor expects one additional arguments: i18n (the i18n service of the current laxarjs bootstrapping context).